As I walked into Stern Pinball's modest facility in Melrose Park, Illinois shortly before Christmas last year, a loud buzzer went off. Dozens of workers streamed past, heading toward a catering cart stationed nearby. It's break time.

This is all that remains of an amusement empire in Chicago last century, an empire that included brands like Williams, Bally, Gottlieb, and Midway, among others. It's an empire that helped build the arcade era. Apart from Stern, everyone else has long since left the pinball business — or gone out of business altogether.

Stern's director of marketing, Jody Dankberg, takes me on a tour of the building, which is quite literally the only manufacturer of pinball machines left in the world (though New Jersey's Jersey Jack Pinball looks close to shipping its first machines). Stern traces its roots back to the 1940s, but it's been through many changes over the years: it was once owned by Japanese firm Data East, then Sega, and now by Gary Stern, the son of a Williams distributor and the company's namesake. I briefly meet Gary, an affable older gentleman, silver-haired, who has all the appearances and mannerisms of a man who's spent an entire lifetime making games.

I learn that each model of Stern's intricate, largely hand-built machines take as much as $1 million and a full year of design, development, and testing before a single unit is boxed up and sent out of the door. Read on to see how these engineering marvels take shape.

Above: In the back of the factory lies a walled-off room, the "Stern Arcade," where employees can play recent releases.